Systems and methods for an amphibious submersible for pipe interior and wall inspection

ABSTRACT

Various embodiments of an amphibious submersible vehicle for use in non-destructive testing of pipe interiors and walls are disclosed herein. In one aspect, the vehicle is operable for amphibious submersible operation such that pipes of various diameters can be inspected under full, partially full, and dry conditions. In another aspect, the vehicle is equipped with a plurality of propellers for travel when fully or partially submerged in water and a plurality of wheels for traveling when in contact with a pipe wall or for traveling over debris. In some embodiments, the vehicle is equipped with a plurality of sensors configured for imaging and navigation which enable the vehicle for pipe inspection and identification of problem areas.

CROSS REFERENCE TO RELATED APPLICATIONS

This is a continuation patent application of U.S. Non-Provisionalapplication Ser. No. 17/201,616 filed on 15 Mar. 2021, now U.S. Pat. No.11,499,665, that claims benefit to U.S. Provisional Patent ApplicationSer. No. 62/989,345 filed 13 Mar. 2020, which is herein incorporated byreference in its entirety.

FIELD

The present disclosure generally relates to non-destructive testing; andin particular, to a system and method for a self-navigating amphibioussubmersible for non-destructive testing of pipe interior and walls.

BACKGROUND

Utility pipe cleaning can cost up to $400,000 per 10 mile segment, withworkers scouring miles-long stretches of pipe to remove debris andidentify problem areas. In some segments, a cleaning hose (˜850 ft.) maynot reach certain areas such as a center of pipe sections. In addition,inspection of pipe structures is a vital task for maintaining the healthof a water system's infrastructure; however, this can also be adangerous task which can be difficult to complete. Thus, it makes senseto identify problem areas in the pipe and focus resources to theseareas.

It is with these observations in mind, among others, that variousaspects of the present disclosure were conceived and developed.

BRIEF DESCRIPTION OF THE DRAWINGS

The patent or application file contains at least one drawing executed incolor. Copies of this patent or patent application publication withcolor drawing(s) will be provided by the Office upon request and paymentof the necessary fee.

FIG. 1 is a perspective view showing an amphibious submersible;

FIG. 2 is a simplified illustration showing internal components of theamphibious submersible of FIG. 1 ;

FIG. 3 is a side view showing a wheel of the amphibious submersible ofFIG. 1 ;

FIG. 4 is an illustration showing the amphibious submersible of FIG. 1traveling along a bottom of a pipe;

FIG. 5 is an illustration showing the amphibious submersible of FIG. 1traveling through the pipe half-filled with water using a first set ofpropellers and a second set of propellers;

FIG. 6 is an illustration showing the amphibious submersible of FIG. 1submerged and traveling through the pipe fully filled with water using afirst set of propellers and a second set of propellers;

FIG. 7 is an illustration showing the amphibious submersible of FIG. 1floating in a full pipe such that the amphibious submersible contacts anupper side of the pipe with the propeller and wheels shown in operation;

FIG. 8 is a diagram showing a controller and associated internalcomponents of the amphibious submersible of FIG. 1 ;

FIG. 9A is a photograph of an exemplary digital sonar imaging sensorincluded onboard the amphibious submersible of FIG. 1 ;

FIGS. 9B and 9C are screenshots of sonar images captured by the digitalsonar imaging sensor of FIG. 9A;

FIG. 10A is a photograph of underwater pipe scanning with a laser usingthe amphibious submersible of FIG. 1 ;

FIG. 10B is an image created by the pipe scanning procedure shown inFIG. 10A; and

FIG. 11 is a graphical representation showing spectroscopy results takenof a pipe by the amphibious submersible of FIG. 1 .

Corresponding reference characters indicate corresponding elements amongthe view of the drawings. The headings used in the figures do not limitthe scope of the claims.

DETAILED DESCRIPTION

Various embodiments of a self-navigating and self-extricating amphibioussubmersible vehicle with visual, sonar and laser sensing capabilitiesare described herein. In one aspect, the vehicle is operable foramphibious submersible operation such that pipes of various diameterscan be inspected under full, partially full, and dry conditions. Inanother aspect, the vehicle is equipped with a plurality of propellersfor navigation when fully or partially submerged in water and aplurality of wheels for traveling when in contact with a pipe substrateor for traveling over debris within the pipe. In some embodiments, thevehicle is equipped with a plurality of sensors operable for imaging andnavigation which enable the vehicle for pipe inspection andidentification of problem areas. In one embodiment, the sensors includevisual, sonar and laser sensors which are operable for determining thelocation, amount and nature of debris, while sonar and laser probingoperations can provide information about wall deposits and pipe wallconditions. Following sensor inspections by the vehicle, targetedcleaning strategies and technologies can be developed. Referring to thedrawings, embodiments of an amphibious submersible, referred to hereinas “the vehicle”, are illustrated and generally indicated as 100 inFIGS. 1-11 .

FIG. 1 illustrates a vehicle 100 that provides an amphibious mobilityplatform to travel through a utility pipe 10 (FIG. 4 ), where aninspection of the utility pipe 10 can be performed by a plurality ofsensors 160 located onboard the vehicle 100. The vehicle 100 is operableto navigate through pipes which may have various obstacles therein, suchas bumps, boulders, and debris under fully filled, partially filled ordry conditions within the interior of the utility pipe 10. Inembodiments, the vehicle 100 includes an elongated body 102 defining afirst side 103, a second side 104, a front side 105 and a rear side 106.A plurality of wheels 110A-D are engaged along respective first andsecond sides 103 and 104 of the elongated body 102. The plurality ofwheels 110A-D of the vehicle 100 are operable for performing amphibiousand terrain maneuvers during submersible operations. Each wheel 110A-Dincludes a plurality of spokes 112 that extend laterally from the centerof each wheel 110A-D, as shown in FIG. 1 . The vehicle 100 furtherincludes a set of horizontally oriented propellers 130A and 130B forforward or backward propulsion when in water, as well as a set ofvertically oriented propellers 132A and 132B for upward or downwardpropulsion of the vehicle 100 in water. In addition, the vehicle 100includes a robotic arm 140 having a sensor array 160 positioned at adistal end of the robotic arm 140 for imaging and navigation through thepipe 10. The motors controlling the wheels 110, the horizontal andvertical propellers 130A, 130B, 132A and 132B, and the robotic arm 140are controlled or otherwise operated by a controller 170 (FIG. 2 ).

Wheels

Referring to FIGS. 1-3 , in some embodiments, each wheel 110A-D ispowered by a respective wheel motor 118A-1180 (FIG. 2 ) for performingamphibious operations and to overcome slippery, granular or otherwiseuneven terrain such as pipe blockages during navigation. For example,one suitable motor is a 12V planetary gear motor capable of a maximumspeed of 45 rpm and stall torque of 153 kgf-cm. In one embodiment, thespokes 112 of wheels 110A-D are interchangeable, thereby allowingvariability between the number of spokes 112 used to reconfigure theshape of the wheel 110 as needed. While traditional wheels are effectiveon flat and solid surfaces, the spokes 112 of each respective wheel110A-D allow for greater traction and maneuverability with lessslippage. In one embodiment, the wheels 110 are used when the vehicle100 is on land (e.g. granular, gravel, and rocky mediums) and wetland(e.g. saturated and muddy environments).

One embodiment of a wheel 110 is illustrated in FIG. 3 . As shown, eachwheel 110 includes a plurality of spokes 112 extending outwardly from ahub 115 of each wheel 110. In this embodiment, each spoke 112 can embodya single member 113 or an anchored member 114. In particular, singlemembers 113 and anchor members 114 are arranged in an alternatingfashion; however, it should be noted that such a configuration is notfixed and that any combination of single members 113 and anchor members114 is contemplated. Anchor members 114 each include a first prong 114Aand a second prong 114B, wherein the first prong 114A and the secondprong 114B are joined together by a rocker 116 positioned at a distalend of the first prong 114A and a distal end of the second prong 114B.In some embodiments, the rocker 116 defines a first claw 117A and asecond claw 117B, each extending past respective junctions with thefirst prong 114A and the second prong 114B. During conditions in whichthe vehicle 100 would need to “drive” on land or saturated ground suchas in FIGS. 4-6 , the first and second claws 117A and 117B of the rocker116 allow the vehicle 100 to anchor itself into the ground and propelitself forward or backward as the wheel 110 is rotated by its associatedmotor 118. This arrangement also enables the vehicle 100 to climb slightgrades on uneven terrain. The arc portion of the rocker 116 allows thevehicle 100 to more easily shift its weight as the vehicle 100 moveseither forward or backward.

Referring to FIG. 2 , wheel motors 118A-D are each associated with arespective wheel 110A-D. In particular, wheel motor 118A is associatedwith wheel 110A for clockwise or counterclockwise rotation of wheel110A, wheel motor 118B is associated with wheel 1108 for clockwise orcounterclockwise rotation of wheel 1108, wheel motor 118C is associatedwith wheel 110C for clockwise or counterclockwise rotation of wheel110C, and wheel motor 118D is associated with wheel 110D for clockwiseor counterclockwise rotation of wheel 110D. Wheel motors 118A-D are eachseparately controlled by the controller 170 (FIG. 8 ) to enabledifferential steering.

Water Propulsion

As noted above, the vehicle 100 is operable for amphibious and fullysubmerged operations. For submerged propulsion, the elongated body 102further includes the set of horizontally oriented propellers 130A and130B engaged on the front side 105 of the vehicle 100 as shown in FIG. 1. Horizontally oriented propellers 130A and 130B point along horizontalaxis X such that rotation of the horizontally oriented propellers 130Aand 130B propels the vehicle 100 in a first direction or an oppositesecond direction along the horizontal axis X. Horizontally orientedpropellers 130A and 130B are each associated with a respectivehorizontally oriented propeller (“H prop”) motor 134A and 134B. Inparticular, H prop motor 134A is associated with horizontally orientedpropeller 130A for clockwise or counterclockwise rotation ofhorizontally oriented propeller 130A, and resultant forward or backwardmotion of the first side 103 of the vehicle 100. Similarly, H prop motor134B is associated with the horizontally oriented propeller 130B forclockwise or counterclockwise rotation of horizontally orientedpropeller 130B, and the resultant forward or backward motion of thevehicle 100. In some embodiments, H prop motors 134A and 134B are eachseparately controlled by controller 170 to enable differential steeringin water.

For propulsion in the vertical direction while submersed, the elongatedbody 102 includes the set of vertically oriented propellers 132A and132B engaged on the front side 105 and the rear side 106 of the vehicle100 as shown in FIG. 1 . Vertically oriented propellers 132A and 132Bare oriented to point along axis Z such that clockwise orcounterclockwise rotation of the vertically oriented propellers 132A and132B propels the vehicle 100 in an upward direction or a downwarddirection along the vertical axis Z. Referring to FIG. 2 , verticallyoriented propellers 132A and 132B are each associated with a respectivevertically oriented propeller (“V prop”) motor 136A and 136B operablefor producing a vertical force when submerged in water such that thevehicle 100 is lifted or lowered within the pipe 10. In particular, Vprop motor 136A is associated with vertically oriented propeller 132Afor clockwise or counterclockwise rotation of vertically orientedpropeller 132A and resultant upward or downward motion of the front side105 of the vehicle 100. Similarly, V prop motor 136B is associated withvertically oriented propeller 132B for clockwise or counterclockwiserotation of vertically oriented propeller 132B and resultant upward ordownward motion of the rear side 106 of the vehicle 100. In someembodiments, V prop motors 134A and 134B are each separately controlledby controller 170 to enable differential steering in the verticaldirection in water. This allows controlled maneuverability in thevertical direction, enabling the vehicle 100 to avoid obstructionswithin the pipe 10.

Ballast

In some embodiments, the vehicle 100 is operable for variable buoyancydue to ballast system 190, which can include an air ballast tank 192associated with an air pump 193 for pumping air into the body 102 of thevehicle 100 and increasing its buoyancy relative to the surroundings ofthe vehicle 100. Similarly, ballast system 190 can also include a waterballast tank 194 associated with a water pump 195 for pumping water intothe body 102 of the vehicle 100 and decreasing its buoyancy relative tothe surroundings of the vehicle 100. In one aspect, the vehicle 100largely operates under neutral buoyancy, which allows better control ina 3-D space.

In a further aspect, three phases are considered for the operation ofthis mobility platform: (1) wheel operation under dry conditions asshown in FIG. 4 , (2) wheel-propeller operation under partiallysubmerged conditions as shown in FIGS. 5 and 6 , and (3) full propellerunder fully submerged conditions as shown in FIG. 7 .

Situational Utility

FIG. 4 illustrates a situation in which the level of liquid in the pipe10 is not so considerable compared to the dimensions of the vehicle 100,and there is enough frictional force between the wheels 110 (FIG. 1 )and a substrate 11 of the pipe to let the vehicle 100 operate by simplerotation of the wheels 110A-D and the vehicle 100 to negotiate obstaclesproperly. As discussed above, the spokes 112 (FIG. 3 ) of each of wheel110 provides sufficient traction such that the vehicle 100 can traverseobstacles.

Referring to FIG. 5 , the second phase corresponds to when the liquidlevel is slightly higher than shown in FIG. 4 to almost, but not fully,submerge the vehicle 100, although not enough to allow the vehicle 100to freely move vertically within the pipe. In this case, the wheels 110may not maintain continual contact with the substrate 11 of the pipe 10,especially if the buoyancy of the vehicle 100 is neutral or slightlyless than that of the surrounding liquid. Therefore, the horizontallyoriented propellers 130A and 130B (FIG. 1 ) and the wheels 110A-D (FIG.1 ) are active and operational during this phase in order to generateenough driving force to propel the vehicle 100 forward or backward.

Referring to FIG. 6 , when the vehicle 100 is fully submerged in thepipe and there is no contact between wheels 110A-D (FIG. 1 ) and thesubstrate 11, the horizontally oriented propellers 130A and 130B (FIG. 1) provide the main driving force to propel the vehicle 100. However, ifthe vehicle 100 encounters obstacles in which the collective forcegenerated by the horizontally oriented propellers 130A and 130B isinsufficient to allow the vehicle 100 to pass over those obstacleswithout contact, the wheels 110A-D of the vehicle 100 would becomeoperational.

Referring to FIG. 7 , when the vehicle 100 is fully submerged andencounters obstacles in which the liquid level in the pipe allows thevehicle 100 sufficient room to move vertically, the vertically orientedpropellers 132A and 132B (FIG. 1 ) are actuated to generate a verticalforce for lifting the vehicle 100 relative to the substrate 11 of thepipe 10. Horizontally oriented propellers 130A and 130B further propelthe vehicle 100 in either a forward or backward direction.

As discussed above, steering of the vehicle 100 in all phases isperformed by applying differential drive to the left and right wheels110. When the wheels 110 are in contact with the substrate 11 of thepipe 10, this method of propulsion is easily applicable. In other cases,when there is no contact between the wheels 110 and the pipe 10,differential rotation is applied to the horizontally or verticallyoriented propellers 130A, 130B, 132A, and 132B to manipulate a positionof the vehicle 100 in 3-D space.

Controller

Referring to FIGS. 2 and 8 , the controller 170 controls motors andother aspects of the vehicle 100. In particular, the controller 170provides individual power and control to the horizontal propeller motors134A and 134B, the vertical propeller motors 136A and 136B, wheel motors118A-118D, robotic arm motors 184A-184D (discussed later herein ingreater detail), and ballast system 190. Controller 170 can alsofacilitate communication with and provide power to the sensor array 160,including one or more sonar sensors 162, a spectroscope 164, one or morenavigation sensors 166, one or more light sources 168, one or morecameras 174, and an associated image transmission module 172 for initialprocessing and transmission of images and other data obtained using thesensor array 160. In some embodiments, the controller 170 includescontrol hardware (not shown) onboard the vehicle 100, and in someembodiments, aspects of the controller 170 are provided via wiredconnection. In one particular embodiment, electronics associated withthe controller 170 are stored onboard the vehicle 100; however, thecontroller 170 is externally controlled by a handheld controller such asa joystick. In some embodiments, power is provided to the controller 170and vehicle 100 by wired connection from power source 176.

Sensors

For visual observation of the interior of the pipe 10, a sensor array160 is installed on the vehicle 100. As shown in FIG. 1 , at least onesensor of the sensor array 160 is mounted at a distal end of the roboticarm 140 of the vehicle 100. The robotic arm 140 includes an arm motorarray 180 and associated arm members 184A and 184B which facilitatemotion of the robotic arm 140 in 6 degrees of motion. In particular, inthe embodiment shown, arm motors 182A and 182B are configured to providetwo degrees of freedom to the first member 184A relative to the body 102of the vehicle 100. Similarly, arm motors 182C and 182D are configuredto provide two degrees of freedom to the second member 184B relative tothe first member 184A, thereby enabling positioning of the sensor array160 with three degrees of freedom.

In some embodiments, the plurality of sensors 160 further include theone or more sonar sensors 162, as shown in FIGS. 8 and 9A-9C. Usingsonar sensors 162, cross-sectional views of the pipe 10 can be rapidlyscanned for debris such that an operator can infer informationconcerning the walls of the pipe 10. The sonar sensor 162 is operable togenerate 360 degree images at high speeds and resolutions, so thatdebris and even wall defects can be visualized regardless of wateroptical conditions.

In some embodiments, the plurality of sensors 160 further includes thespectroscope 164 operable for obtaining spectral data fromlaser-illuminated surfaces as shown in FIGS. 10A-11 . The spectroscope164 is operable for scanning the walls of the pipe 10, and thereflectance can then be spectrally analyzed for pipe wall deposit andother surface conditions. Laser scanning can easily identify walldefects, due to its high resolution (<1 mm). Defects such de-bondedjoints, wall erosion, and deposits can be detected.

Positioning of the vehicle 100 is an important task which is necessaryto determine the location of any problem areas along the pipes 10. Ithas been found that Global Positioning System (GPS) does not work inthis case because the underground nature of the environment blocks theGPS signal. Therefore, the vehicle 100 employs local positioning methodsto navigate. Among possible options, the vehicle 100 uses an inertialmeasurement unit (IMU) 166 as a base sensor to measure the position ofthe vehicle 100. An IMU 166 is an electronic device that measures abody's specific force, angular rate, and sometimes the magnetic fieldsurrounding the body. A major disadvantage of using IMUs is that theytypically suffer from accumulated error. With the guidance systemcontinually integrating acceleration with respect to time to calculateposition and velocity, any measurement errors, are accumulated over timeand leads to “drift”. A Kalman filter (not shown) in combination withother positional tracking systems can be used to continually correctdrift errors. In some embodiments, the plurality of sensors 160 includea compact underwater light source 168 mounted on the vehicle 100. Insome embodiments, a camera 174 and image transmission/data recordingmodule 172 are included on the vehicle 100 which are both compact andsubmersible.

It should be understood from the foregoing that, while particularembodiments have been illustrated and described, various modificationscan be made thereto without departing from the spirit and scope of theinvention as will be apparent to those skilled in the art. Such changesand modifications are within the scope and teachings of this inventionas defined in the claims appended hereto.

What is claimed is:
 1. A vehicle, comprising: an elongated body defininga first side, an opposite second side, a front side, and a rear side;one or more propellers and a plurality of wheels associated with theelongated body, the one or more propellers and the plurality of wheelsbeing collectively operable for propelling the vehicle in at least oneof a vertical direction and a horizontal direction; and a sensor arrayassociated with the vehicle, wherein the sensor array is operable forimaging and navigation of the vehicle.
 2. The vehicle of claim 1,wherein the sensor array includes at least one of: one or more sonarsensors; a spectrometer; and one or more navigation sensors.
 3. Thevehicle of claim 1, wherein the one or more propellers includes avertically oriented propeller configured to propel the vehicle in thevertical direction within a liquid surrounding the vehicle, thevertically oriented propeller being associated with a respectivevertically oriented propeller motor in operative communication with acontroller.
 4. The vehicle of claim 1, wherein the one or morepropellers includes a horizontally oriented propeller configured topropel the vehicle in the horizontal direction within a liquidsurrounding the vehicle, the horizontally oriented propeller beingassociated with a respective horizontally oriented propeller motor inoperative communication with a controller.
 5. The vehicle of claim 1,wherein each wheel of the plurality of wheels is associated with arespective wheel motor of a plurality of wheel motors in operativecommunication with a controller such that each respective wheel motor isoperable for rotation independent of one another.
 6. The vehicle ofclaim 1, further comprising a ballast system, wherein the ballast systemis operable for increasing or decreasing the buoyancy of the vehiclerelative to an external environment of the vehicle.
 7. The vehicle ofclaim 1, wherein one or more sensors of the sensor array are positionedalong a robotic arm extending from the elongated body and wherein therobotic arm is operable for motion along six degrees of freedom.
 8. Avehicle, comprising: an elongated body defining a first side, anopposite second side, a front side, and a rear side; one or morepropellers and a plurality of wheels associated with the elongated body,the one or more propellers and the plurality of wheels beingcollectively operable for propelling the vehicle in at least one of avertical direction and a horizontal direction, wherein each wheel of theplurality of wheels includes a plurality of spokes, wherein at least twospokes of the plurality of spokes are coupled at a rocker and whereinthe rocker includes at least one claw; and a sensor array associatedwith the vehicle, wherein the sensor array is operable for imaging andnavigation of the vehicle.
 9. The vehicle of claim 8, wherein the sensorarray includes at least one of: one or more sonar sensors; aspectrometer; and one or more navigation sensors.
 10. The vehicle ofclaim 8, wherein the one or more propellers includes a verticallyoriented propeller configured to propel the vehicle in the verticaldirection within a liquid surrounding the vehicle, the verticallyoriented propeller being associated with a respective verticallyoriented propeller motor in operative communication with a controller.11. The vehicle of claim 8, wherein the one or more propellers includesa horizontally oriented propeller configured to propel the vehicle inthe horizontal direction within a liquid surrounding the vehicle, thehorizontally oriented propeller being associated with a respectivehorizontally oriented propeller motor in operative communication with acontroller.
 12. The vehicle of claim 8, wherein each wheel of theplurality of wheels is associated with a respective wheel motor of aplurality of wheel motors in operative communication with a controllersuch that each respective wheel motor is operable for rotationindependent of one another.
 13. The vehicle of claim 8, furthercomprising a ballast system, wherein the ballast system is operable forincreasing or decreasing the buoyancy of the vehicle relative to anexternal environment of the vehicle.
 14. The vehicle of claim 8, whereinone or more sensors of the sensor array are positioned along a roboticarm extending from the elongated body and wherein the robotic arm isoperable for motion along six degrees of freedom.
 15. A method formaneuvering a vehicle within a pipe, comprising: providing a vehicle,comprising: an elongated body defining a first side, an opposite secondside, a front side, and a rear side; one or more propellers and aplurality of wheels associated with the elongated body, the one or morepropellers and the plurality of wheels being collectively operable forpropelling the vehicle in at least one of a vertical direction and ahorizontal direction; a sensor array associated with the vehicle,wherein the sensor array is operable for imaging and navigation of thevehicle; actuating at least one of the one or more propellers and theplurality of wheels resulting in propulsion of the vehicle in at leastone of a horizontal direction and a vertical direction; generating aspectral image of an interior of a pipe by a spectroscope of the sensorarray; and generating a sonar image of an interior of a pipe by one ormore sonar sensors of the sensor array.
 16. The method of claim 15,further comprising: actuating a vertically oriented propeller of the oneor more propellers resulting in propulsion of the vehicle in thevertical direction.
 17. The method of claim 15, further comprising:actuating a horizontally oriented propeller of the one or morepropellers resulting in propulsion of the vehicle in the horizontaldirection.
 18. The method of claim 15, further comprising: activatingone or more pumps of a ballast system of the vehicle resulting in anincrease in buoyancy or a decrease in buoyancy of the vehicle.
 19. Themethod of claim 15, further comprising: orienting the sensor array in3-dimensional space by actuating one or more arm motors associated witha robotic arm of the vehicle, wherein the sensor array is located at adistal end of the robotic arm.
 20. The method of claim 15, furthercomprising: actuating the one or more wheels when a collective forcegenerated by one or more horizontally oriented propellers of the one ormore propellers is insufficient to overcome one or more obstacles withinan external environment of the vehicle.